New to Linux - need help downloading ISPConfig

I'm new to Linux and command lines. I followed the instructions in the howto "The Perfect Server - Fedora 7" and have reached the point to install ISPConfig. But, I can't find instructions on how to download ISPConfig using a command line. Please help!

Yep. Thanks to advice I've downloaded and unzipped the file to a /download directory that I created specially. And yes, when I look, lo and behold ls /download/install_ispconfig/ reveals that there is a file called setup. Excellent.

As I have never run anything like this before please, how do I actually install ISPConfig from the files I have got and what directory should I put the installation into, or does it do it 'all on its own'?

Only one thing though. At the final questions section I entered the host name as 'www' which I believe is ok - it shows that in the installation instructions you sent the link for - but, and here's my mistake I think, for the next question, 'Please enter the domain' I entered the name of my current website (xxxxxxxxxxx.com). That does not work of course as that is already being hosted by a commercial company. The problem is that I now cannot log in to my ISPConfig control panel. I presume that there is a configuration file somewhere where I can edit out my mistake and replace it with something else. Can you point me to where please, and does the 'something else have to be entirely fictitious or one that is registered. I have an unused (not hosted anywhere) .co.uk name that I could use if necessary.